John Romero, designer

After all the success we had with Wolfenstein and the Commander Keen games, there was huge speculation about what our followup would be. Someone even came up with an acronym for their own fantasy version of it: SPISPOPD, which stood for Smashing Pumpkins into Small Piles of Putrid Debris. And then someone actually made that game.

We started work on something new in January 1993, putting out a press release announcing all the revolutionary things it was going to do: we said we fully expected it to cause the biggest loss of productivity in the world ever.

Then one day we were playing Dungeons & Dragons at the HQ of our company, id Software, like we had done for years. John Carmack, lead programmer, was Dungeon Master as usual. I got greedy trying to procure a magic sword and caused the entire world to be overrun by demons. Something just clicked. We all loved sci-fi, especially Aliens: it was a fast-action movie and id wanted fast-action games. So what if – instead of finding aliens, like in every movie in the world – a player opened up a portal to hell? Your character, a space marine on a Martian base, would then have to fight all the demonic monsters pouring out.

First-person shooter games became huge because players could identify directly with the character, but early versions had to be designed around limited speeds. The advent of Intel's 386 microprocessor finally gave us more horsepower: we could start making stuff move fast. Carmack put in as many new features as possible: irregular walls, sloping floors, changing light levels. The aim was to be cool and realistic – but also fast. We wanted to make it the most fun thing we could ever think of playing. There can't be a more fun game in the world.

I wrote the programme behind all the levels, and did a lot of the design and audio work. The artists kept Necronomicon, a book of images by the Swiss surrealist HR Giger, open in front of them, to help them come up with crazy disturbing stuff. That's why we have walls that are like spines and screaming faces, and marines impaled on spikes. It inspired hellish monsters, too, like the cacodemon – the one that flies, shoots lightning and then spills its blue guts out when it dies. It looks very cartoon-like today, but it was the coolest thing when it came out.

We were criticised after the Columbine shootings, but we knew it wasn't our fault. There have been violent games since the 1800s, when you could put a coin in a penny arcade and watch an execution scene play out. I was like: I'm not getting caught up in this age-old debate. I didn't comment on any of it. Whatever the new thing is, people always blame that – Judas Priest, Ozzy, comic books. But the big problem is people not being in touch with their kids.

Tom Hall, creative director

We got the title from The Color of Money – the bit where Tom Cruise explains what he keeps in his pool-cue case. At the very start, I wrote a framing story that began with a demon bursting in on a bunch of soldiers having a card game and killing everyone but the player. I wanted more story throughout to heighten the sense of dread. But id was undergoing a big change: technological advances were now dictating videogames. So for Doom to be landmark, it had to put graphics first. My story stuff – which was used as a structure, but never explicitly told – was a few years too early: the Half-Life games, the next landmark first-person shooters, were more like the sort of thing I had in mind.

Lots of my ideas got used, but others were rejected piecemeal: score was out, characters were out, a sense of real-life, functional rooms were out. In the end, I only designed seven levels. Meanwhile, Romero was doing brilliant stuff, creating those big, tall, abstract levels that defined the Doom aesthetic. He was in the zone, bonded together with the other creatives in heavy-metal demonville.

In the early days of id, we were like the limbs of one big creature, working brilliantly in parallel. But I now felt isolated. We worked 14 to 16 hours a day, seven days a week, with little outside contact. Taking a weekend off was looked on with disdain. Playing fighting games, often on the [rare Japanese console] Neo-Geo, was one of our few releases. Also, there always seemed to be a scapegoat, a "shitboy". It was usually anyone at the company for a short while. Then it was me.

We were all great friends and obsessed with making games but, in the end, bad working relationships and horrible communication on both sides put me in creative molasses. You can't afford that with a small team. Romero had me over for dinner the night before a shareholder meeting, but he couldn't bring himself to warn me. The next day I was told: "It isn't working out." I was surprised. I felt some shame and some fear – but they'd already talked to another firm so I had somewhere to go. It felt like a huge weight off my shoulders.

Some of my stuff is in its skeleton, but Doom is almost 100% meat. Minecraft is the only recent game to have matched its minimalist raw cool. Doom deserves every bit of praise it gets.